The General Packet Radio Service (GPRS) supports data communication in cellular networks. In Third Generation (3G) and Long Term Evolution (LTE) cellular networks, data communication is exchanged using the GPRS Tunneling Protocol (GTP). The user data tunneling part of the GTP protocol (GTP-U) is used over interfaces between access points (base-stations) and core network entities in many types of cellular networks, including over IuB interfaces in Universal Mobile Telecommunication Systems (UMTS), IuH interfaces in 3G networks, and S1 interfaces in LTE networks. In 3G networks, the GTP-U is applied to all data traffic but not to voice traffic, which is carried outside GTP-U tunnels. In LTE networks, GTP-U may be applied to voice traffic (i.e., voice traffic can be carried inside a GTP tunnel), depending on the Voice over LTE (VoLTE) model used.
The interfaces between access points and core network entities may span large distances, over various types of links. When a satellite link or other high latency link is used for backhauling interfaces between access points and core networks entities (like the IuB, IuH, and S1 interfaces), traffic between access points and core network entities is subjected to high latency. Unfortunately, subjecting traffic to high latency often leads to performance degradation. In order to mitigate or prevent performance degradation and poor user experience, transmission Control Protocol (TCP) acceleration methods, Hyper Text Transfer Protocol (HTTP) acceleration methods, and/or various caching methods may be applied.
Satellite bandwidth is a limited resource with significant usage costs. Thus, cellular traffic backhauled over a satellite link should be backhauled in an efficient manner to minimize operation costs. Voice over IP (VoIP) traffic is often characterized by small packets with relatively high overhead. Transmitting VoIP traffic “as is” over a satellite link is likely to result in significantly inefficient utilization of the satellite resource. Accordingly, it may be desirable to identify and treat voice traffic (e.g., to minimize delay, jitter, packet loss, and/or overhead) to prevent degradation in voice quality and/or achieve more efficient utilization of satellite resources.
While there are known technologies for TCP acceleration, HTTP acceleration, caching, and VoIP treatment, they may be less effective when the traffic is encapsulated with tunneling information. A significant challenge exists in applying acceleration and caching methods to traffic encapsulated with tunneling information.
Examples of known technologies for acceleration, caching, and VoIP treatment are described in U.S. Pat. No. 6,947,440, to Chatterjee et al. and U.S. Pat. No. 8,837,349 to Yabo et al.